I always write thank you notes. I don't care if people write them to me, I just feel like if someone gives me or my children a gift, I write a note. There comes that time around six when the children are supposed to write them. I realized quickly it was going to take months for us to write all the notes from my oldest daughter's 6th birthday party and too much frustration to really be worth it. So I decided to take a different approach. Why don't I let her draw what she was given? I have found this so much more pleasant...recognizing the outcome is definitely messy and well, personalized stationary probably not necessary!
If you do want to go the personalized stationary route, here are some of my favorites for kids: Fontaine Maury, iomoi, and Dabney Lee.